Cita APA (7th ed.)

Russwurm, L. H., & Sommerville, E. (1974). Man's natural environment: A systems approach. Duxbury Press.

Cita Chicago (17th ed.)

Russwurm, Lorne H., i Edward Sommerville. Man's Natural Environment: A Systems Approach. North Scituate, Mass.: Duxbury Press, 1974.

Cita MLA (8th ed.)

Russwurm, Lorne H., i Edward Sommerville. Man's Natural Environment: A Systems Approach. Duxbury Press, 1974.